What If the Universe Collapsed in on Itself?

Hear that? That's the sound of the universe collapsing in on itself. We only have a few minutes until it's self destruction sequence is over. This is what the end of times might just look like. What could possibly 'cause this intergalactic damage? How could humans help prevent this event? And what would come next after this universal destruction? This is what if, and here's what would happen if the universe collapsed in on itself. We've killed the universe before. It went through the Big Crunch and the Big Rip and the heat death, and now it's time for the most efficient cosmic death, the vacuum decay. The universe might seem vast, cold and empty, but it's filled with all sorts of stuff invisible to your naked eye. One of the things filling the universe is called the Higgs field. It's associated with the Higgs boson, which you may have heard about. It used to be a strictly theoretical elementary particle until researchers observed it in the Large Hadron Collider almost a decade ago. And even though we can't see the Higgs field, it could one day destroy the entire universe. So what's the deal with this Higgs field, and why could it cause the biggest catastrophe of all space and time? Everything on Earth and in space has potential energy. It's this energy that every object stores depending on factors like its state and its position. Everything wants to be in a stable state, which implies storing as little energy as possible, or as scientists call it, being in the true vacuum state. As with any quantum field, the Higgs field could already be in that true vacuum state. This would mean our universe is as stable as it gets, and no Higgs field would threaten our existence. But there are reasons to believe the Higgs field isn't actually in a stable true vacuum state. Instead, it's pretending to be in one while having a lot of potential energy waiting to 'cause our doom. And this state is called a false vacuum. It seems stable, but it's a false sense of security. If the Higgs field suddenly lost some of its energy, even in the tiniest point in space, it would mean the release of all that extra energy back into the universe. It would create a sort of bubble of the true vacuum state inside it, and that bubble would start devouring the universe at the speed of light. Inside this doomsday bubble, the universe wouldn't be the universe we once knew. The very fabric of our universe would be torn up and changed. Atoms would cease to be atoms, and all of our fundamental constants, such as the speed of light, would be completely different. How would we know this energetic death of the universe was coming our way? Well, the speed of light might be fast, but the universe is incredibly vast. It would take time for the bubble of Doom to reach us, depending on where it first appeared. But if you noticed distant galaxies getting ripped apart and behaving in ways against all the laws of physics, you'd know the bubble was coming for us next. By the time it reached our corner of the universe, it would be so big and energetic that nothing would be able to stop it. You wouldn't be able to do anything but watch the Earth die. And there's a possibility that in the end, the entire universe could collapse into one gigantic black hole. Game over. Of course, even if the Higgs field is in a false vacuum state, it won't collapse anytime soon. The universe has survived long before us, and it will exist in some form long after humanity is gone, although our extinction could happen sooner than you might expect. But that's a story for another What if?